1. Field of the Invention
The present invention relates to a range-finding device configured to measure a distance to a subject to be photographed, and an imaging apparatus such as a digital still camera, a digital video camera, and the like, which has the range-finding device.
2. Description of the Related Art
As a digital still camera (referred to as a digital camera, hereinafter) having an autofocus (AF) function, a range-finding device in which an outer measurement triangulation system is applied is conventionally known (see Japanese Patent Application Publication No. 2002-90616).
The range-finding device having a triangulation system includes a pair of range-finding lenses disposed at a predetermined interval and a pair of planar range-finding image pickup units on which subject images are formed through the range-finding lenses, respectively. By detecting a disparity between the subject images formed on the range-finding image pickup units based on pixel output signal output from the range-finding image pickup units, respectively, a distance to the subject to be photographed can be obtained.
In the range-finding device using the triangulation system as described in Japanese Patent Application Publication No. 2002-90616, in order to perform range-finding with high accuracy, it is necessary that the range-finding image pickup units are accurately arranged at predetermined positions and arranged in a planar state so as to avoid angle deviation (inclination) on light receiving surfaces of the range-finding image pickup units.
Therefore, conventionally, during assembling the range-finding device, when the separately formed image pickup unit is arranged on a substrate, it is required to correct positional and angle deviations of the range-finding image pickup units to cause worsened work efficiency.